right. but a shield is just the outer metal core on the 1/4 inch jack right? this cable has that.

i made another circuit with a 556. and grounded it the way audioguru told me, and it works fine.

it might also be worth noting that even when connected to a small 8 ohm speaker as opposed to the amp, I still get the radio station. So, it may not be the grounding with the audio connection that's the problem.

 

You may be near a radio station, where the field strength is really strong. Use bypass capacitors (around 0.1µF) on the power supply, on pin 5, and if all else fails, on the outputj (this is drastic, and not recommended normally).

If the station is within a ½ mile away maybe you can light up and LED with it, and really piss of the station manager and technician.

 

i have done similar filter things in the past, i never knew why it worked, and was pretty sure it wasn't the best way to do it. i'm pretty sure there are lots of radio stations within a half mile radius. I didn't get any radio stations at band practice, it worked this time btw. There is however a police precinct down the street and we tried to pick that up but nothin.

when you say on the power supply, do you mean between + and ground? and on pin 5, between pin5 and anything else connected to it? i would imagine between the outputs would cut the output significantly?

 

Pin 8 and Pin 1 are the power supply pins, pin 4 should also be connected to pin 8, but it is a reset pin for the 555. Basically you're trying to short circuit any radio frequencies floating around your circuitry. Without see your setup we are stuck with giving generic advice in many cases.

BTW, if you just put a long wire on the input of the amplifier (leaving your circuit out of the loop) do you still get the radio station? I am assuming an AM station, as that is the norm for several reasons.